<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

</head>
<body>

<iframe src="https://baidu.com"
        width="500" height="500" frameborder="0"
        allowfullscreen sandbox>
    <p><a href="https://baidu.com">
        Fallback link for browsers that don't support iframes
    </a></p>
</iframe>

<audio controls>
    <source src="viper.mp3" type="audio/mp3">
    <source src="viper.ogg" type="audio/ogg">
    <p>Your browser doesn't support HTML5 audio. Here is a <a href="viper.mp3">link to the audio</a> instead.</p>
</audio>

<video src="rabbit320.webm" controls>
    <p>Your browser doesn't support HTML5 video. Here is a <a href="rabbit320.webm">link to the video</a> instead.</p>
</video>
<p>
    我是一张图片
    <br>
    <!--img 是内联元素-->
    <img
         src="https://upload.wikimedia.org/wikipedia/commons/thumb/6/61/HTML5_logo_and_wordmark.svg/240px-HTML5_logo_and_wordmark.svg.png">
</p>


</body>
</html>